Highest temperature in Shenzhen on August 20?

Platform comparison

Market context

Shenzhen will experience peak summer heat on 20 August 2026, with the highest daily temperature recorded at Bao'an International Airport determining the settlement outcome. The market resolves using Weather Underground's Daily Observations table rather than the summary high-low display, a distinction that matters when automated systems scrape weather data—the granular observation log often captures brief temperature spikes the summary misses. Traders building conditional order logic should flag this resolution source explicitly, as API integrations typically default to the more accessible summary fields.

August represents Shenzhen's hottest month, with historical daily maxima clustering between 32–34°C, though readings occasionally exceed 35°C during heat waves. The 0% crowd probability suggests either extreme confidence in a specific temperature band or insufficient liquidity attracting serious positioning. Comparable August dates from 2015–2023 show only three instances of temperatures below 31°C, all occurring during typhoon systems that disrupted normal heating patterns. This historical distribution provides a baseline for calibrating range probabilities programmatically.

Tropical cyclone activity remains the primary catalyst affecting August temperatures in the Pearl River Delta region. The China Meteorological Administration issues seasonal forecasts in July, and real-time typhoon tracking from the Joint Typhoon Warning Center becomes actionable in the final fortnight before settlement. Traders monitoring conditional orders should integrate CMA advisories and track upper-atmosphere pressure systems from early August onwards, as even systems passing south of Shenzhen can suppress daytime maxima by 2–3°C through cloud cover and moisture advection.

Methodology

We track Highest temperature in Shenzhen on August 20? across the five venues with material prediction-market liquidity. The probability shown is the live Polymarket mid; the comparison rows summarise how each venue treats the underlying contract — fees, KYC thresholds, settlement currency, deposit options. The highlighted row marks the cheapest route into Polymarket's order book.

Resolution & payout

At resolution the UMA oracle takes over: a proposer posts the outcome with a bond, any token holder can dispute within two hours. Without dispute the result is accepted and the smart contract distributes USDC instantly.

On Kalshi (CFTC-regulated) resolution runs through their in-house clearing engine in USD. Betfair Exchange settles after match end in the account's local currency. Manifold pays no cash — only its in-platform "mana" currency.

UK Frequently Asked Questions

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How does resolution work?

Through the UMA Optimistic Oracle on Polygon: a proposer submits the outcome, a two-hour challenge window opens, and USDC payouts settle automatically once the result is final.

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Polymarket is accessible to UK traders but is not UKGC-licensed. It operates under US CFTC jurisdiction. UK residents face no domestic legal prohibition on using it, but UKGC consumer protections do not apply. For UKGC-regulated alternatives, Betfair Exchange and Smarkets offer similar prediction-style markets.

Do I pay tax on prediction market profits in the UK?

UKGC-licensed platform profits (Betfair, Smarkets) are typically tax-free gambling winnings for UK individuals. Polymarket profits involve USDC crypto transactions, which HMRC treats as Capital Gains Tax events. Keep full transaction records and report via Self Assessment if gains exceed £3,000 per tax year.

How do I deposit on Polymarket from the UK?

UK traders typically fund Polymarket via Coinbase UK, Kraken or Revolut — buying USDC with GBP and transferring to a Polygon-compatible wallet (MetaMask, Coinbase Wallet). Polymarket's onboarding walks you through the bridging process. Typical GBP-to-USDC conversion costs 0.5–1%.